Asero R
Ambulatorio di Allergologia, Ospedale Caduti Bollatesi, Bollate, Italy.
Clin Exp Allergy. 1998 Nov;28(11):1368-73. doi: 10.1046/j.1365-2222.1998.00399.x.
Most patients with birch pollen allergy report oral allergy symptoms after eating fresh apples and other vegetable foods. Major birch pollen and apple allergens, Bet v 1 and Mal d 1, are highly homologous; as a consequence, pollen-specific immunotherapy (SIT) might be expected to improve apple hypersensitivity.
To evaluate the clinical and immunological effects of birch pollen SIT on oral allergy syndrome (OAS) induced by apples.
A prospective study carried out in 49 birch pollen-sensitive patients with apple-induced OAS who received injection immunotherapy for 12, 24, or 36 months. Twenty-six patients not submitted to SIT and followed up for 12-48 months were used as controls. Both SPT and open oral challenges with fresh golden delicious apple were performed, as well as specific IgE measurements, before and after SIT.
Forty-one patients (84%) vs no control (0%) reported a significant reduction (50-95%) or a total disappearance (100%) of OAS symptoms after SIT (P < 0. 001). Similar responses were observed in patients treated for 12, 24, or 36 months. SIT also induced a marked reduction in skin reactivity against fresh apple in 43 patients (88%). The effect of SIT was inversely related with baseline skin reactivity: 50% and 8% patients with a weakly or strongly positive baseline apple skin prick tests (SPT), respectively, did not report changes in OAS severity after SIT (P < 0.01). In contrast, baseline birch pollen-specific or apple-specific IgE antibodies levels did not influence SIT effectiveness on OAS. SIT induced a marked decrease in birch pollen-specific IgE levels (P < 0.001), whereas apple-specific IgE showed an unexpected variability (reduction in 21%, no change in 43%, increase in 38%). No control subject reported a reduction in OAS severity or showed a decrease in skin reactivity at follow-up (P < 0.001).
SIT with birch pollen extracts effectively reduces clinical apple sensitivity and skin reactivity in most cases after only 1 year of treatment; these effects are not paralleled by a similar reduction in apple-specific IgE. These findings suggest a decrease in activability of effector cells as the mechanism underlying clinical benefit.
大多数桦树花粉过敏患者在食用新鲜苹果和其他蔬菜类食物后会出现口腔过敏症状。主要的桦树花粉和苹果过敏原，即Bet v 1和Mal d 1，具有高度同源性；因此，花粉特异性免疫疗法（SIT）可能有望改善对苹果的过敏反应。
评估桦树花粉SIT对苹果诱发的口腔过敏综合征（OAS）的临床和免疫学效果。
对49例对桦树花粉敏感且患有苹果诱发的OAS的患者进行前瞻性研究，这些患者接受了12、24或36个月的注射免疫疗法。26例未接受SIT且随访12 - 48个月的患者作为对照。在SIT前后均进行了皮肤点刺试验（SPT）和用新鲜金冠苹果进行的开放性口服激发试验，以及特异性IgE检测。
41例患者（84%）在SIT后报告OAS症状显著减轻（减轻50 - 95%）或完全消失（100%），而对照组无一例（0%）出现这种情况（P < 0.001）。在接受12、24或36个月治疗的患者中观察到类似的反应。SIT还使43例患者（88%）对新鲜苹果的皮肤反应性显著降低。SIT的效果与基线皮肤反应性呈负相关：基线苹果皮肤点刺试验（SPT）弱阳性或强阳性的患者中，分别有50%和8%在SIT后OAS严重程度未报告变化（P < 0.01）。相比之下，基线桦树花粉特异性或苹果特异性IgE抗体水平并不影响SIT对OAS的疗效。SIT使桦树花粉特异性IgE水平显著降低（P < 0.001），而苹果特异性IgE呈现出意外的变异性（降低21%，无变化43%，升高38%）。随访时，对照组无一例报告OAS严重程度减轻或皮肤反应性降低（P < 0.001）。
仅经过1年治疗，大多数情况下，用桦树花粉提取物进行SIT可有效降低对苹果的临床敏感性和皮肤反应性；这些效果并未伴随着苹果特异性IgE的类似降低。这些发现表明效应细胞的激活能力降低是临床获益的潜在机制。
